Commitments and Contingencies - Financial Instruments with Off-Balance-Sheet Risk (Detail) - USD ($) $ in Thousands |
Mar. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Standby Letters of Credit [Member] | ||
| Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] | ||
| Financial instruments with off- balance-sheet risk | $ 423,163 | $ 449,176 |
| Deferred Standby Letter Of Credit Fees [Member] | ||
| Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] | ||
| Financial instruments with off- balance-sheet risk | 2,457 | 3,071 |
| Commitments to Extend Credit [Member] | ||
| Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] | ||
| Financial instruments with off- balance-sheet risk | $ 11,808,656 | $ 12,046,520 |